There is a growing need in the world as we find it for both improved security and for improved communication capability. In many areas of the cities, in public transportation, on the highways, in large buildings after business hours, and in many other situations and areas, there is the occasional need to give an urgent alarm.
Because of the lack of this capability in areas such as deserted streets after dark and public transportation, such areas have become prime spots for the activities of violent criminals. If there were a system which made it possible for individuals to give an instant alarm, criminal activity would be greatly suppressed.
Furthermore, the need for signaling and communication goes beyond criminal activity. A security and communication net which covers a large area could be used in a multitude of ways for safety, as well as for other priority or urgent communication.